chelsio: more rx speedup
[safe/jmp/linux-2.6] / drivers / net / spider_net.c
index 2154469..d73018b 100644 (file)
@@ -21,8 +21,6 @@
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#include <linux/config.h>
-
 #include <linux/compiler.h>
 #include <linux/crc32.h>
 #include <linux/delay.h>
@@ -30,6 +28,7 @@
 #include <linux/ethtool.h>
 #include <linux/firmware.h>
 #include <linux/if_vlan.h>
+#include <linux/in.h>
 #include <linux/init.h>
 #include <linux/ioport.h>
 #include <linux/ip.h>
@@ -43,6 +42,7 @@
 #include <linux/slab.h>
 #include <linux/tcp.h>
 #include <linux/types.h>
+#include <linux/vmalloc.h>
 #include <linux/wait.h>
 #include <linux/workqueue.h>
 #include <asm/bitops.h>
@@ -55,12 +55,13 @@ MODULE_AUTHOR("Utz Bacher <utz.bacher@de.ibm.com> and Jens Osterkamp " \
              "<Jens.Osterkamp@de.ibm.com>");
 MODULE_DESCRIPTION("Spider Southbridge Gigabit Ethernet driver");
 MODULE_LICENSE("GPL");
+MODULE_VERSION(VERSION);
 
 static int rx_descriptors = SPIDER_NET_RX_DESCRIPTORS_DEFAULT;
 static int tx_descriptors = SPIDER_NET_TX_DESCRIPTORS_DEFAULT;
 
-module_param(rx_descriptors, int, 0644);
-module_param(tx_descriptors, int, 0644);
+module_param(rx_descriptors, int, 0444);
+module_param(tx_descriptors, int, 0444);
 
 MODULE_PARM_DESC(rx_descriptors, "number of descriptors used " \
                 "in rx chains");
@@ -84,15 +85,14 @@ MODULE_DEVICE_TABLE(pci, spider_net_pci_tbl);
  *
  * returns the content of the specified SMMIO register.
  */
-static u32
+static inline u32
 spider_net_read_reg(struct spider_net_card *card, u32 reg)
 {
-       u32 value;
-
-       value = readl(card->regs + reg);
-       value = le32_to_cpu(value);
-
-       return value;
+       /* We use the powerpc specific variants instead of readl_be() because
+        * we know spidernet is not a real PCI device and we can thus avoid the
+        * performance hit caused by the PCI workarounds.
+        */
+       return in_be32(card->regs + reg);
 }
 
 /**
@@ -101,47 +101,14 @@ spider_net_read_reg(struct spider_net_card *card, u32 reg)
  * @reg: register to write to
  * @value: value to write into the specified SMMIO register
  */
-static void
+static inline void
 spider_net_write_reg(struct spider_net_card *card, u32 reg, u32 value)
 {
-       value = cpu_to_le32(value);
-       writel(value, card->regs + reg);
-}
-
-/**
- * spider_net_write_reg_sync - writes to an SMMIO register of a card
- * @card: device structure
- * @reg: register to write to
- * @value: value to write into the specified SMMIO register
- *
- * Unlike spider_net_write_reg, this will also make sure the
- * data arrives on the card by reading the reg again.
- */
-static void
-spider_net_write_reg_sync(struct spider_net_card *card, u32 reg, u32 value)
-{
-       value = cpu_to_le32(value);
-       writel(value, card->regs + reg);
-       (void)readl(card->regs + reg);
-}
-
-/**
- * spider_net_rx_irq_off - switch off rx irq on this spider card
- * @card: device structure
- *
- * switches off rx irq by masking them out in the GHIINTnMSK register
- */
-static void
-spider_net_rx_irq_off(struct spider_net_card *card)
-{
-       u32 regvalue;
-       unsigned long flags;
-
-       spin_lock_irqsave(&card->intmask_lock, flags);
-       regvalue = spider_net_read_reg(card, SPIDER_NET_GHIINT0MSK);
-       regvalue &= ~SPIDER_NET_RXINT;
-       spider_net_write_reg_sync(card, SPIDER_NET_GHIINT0MSK, regvalue);
-       spin_unlock_irqrestore(&card->intmask_lock, flags);
+       /* We use the powerpc specific variants instead of writel_be() because
+        * we know spidernet is not a real PCI device and we can thus avoid the
+        * performance hit caused by the PCI workarounds.
+        */
+       out_be32(card->regs + reg, value);
 }
 
 /** spider_net_write_phy - write to phy register
@@ -199,60 +166,33 @@ spider_net_read_phy(struct net_device *netdev, int mii_id, int reg)
 }
 
 /**
- * spider_net_rx_irq_on - switch on rx irq on this spider card
- * @card: device structure
- *
- * switches on rx irq by enabling them in the GHIINTnMSK register
- */
-static void
-spider_net_rx_irq_on(struct spider_net_card *card)
-{
-       u32 regvalue;
-       unsigned long flags;
-
-       spin_lock_irqsave(&card->intmask_lock, flags);
-       regvalue = spider_net_read_reg(card, SPIDER_NET_GHIINT0MSK);
-       regvalue |= SPIDER_NET_RXINT;
-       spider_net_write_reg_sync(card, SPIDER_NET_GHIINT0MSK, regvalue);
-       spin_unlock_irqrestore(&card->intmask_lock, flags);
-}
-
-/**
- * spider_net_tx_irq_off - switch off tx irq on this spider card
+ * spider_net_rx_irq_off - switch off rx irq on this spider card
  * @card: device structure
  *
- * switches off tx irq by masking them out in the GHIINTnMSK register
+ * switches off rx irq by masking them out in the GHIINTnMSK register
  */
 static void
-spider_net_tx_irq_off(struct spider_net_card *card)
+spider_net_rx_irq_off(struct spider_net_card *card)
 {
        u32 regvalue;
-       unsigned long flags;
 
-       spin_lock_irqsave(&card->intmask_lock, flags);
-       regvalue = spider_net_read_reg(card, SPIDER_NET_GHIINT0MSK);
-       regvalue &= ~SPIDER_NET_TXINT;
-       spider_net_write_reg_sync(card, SPIDER_NET_GHIINT0MSK, regvalue);
-       spin_unlock_irqrestore(&card->intmask_lock, flags);
+       regvalue = SPIDER_NET_INT0_MASK_VALUE & (~SPIDER_NET_RXINT);
+       spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK, regvalue);
 }
 
 /**
- * spider_net_tx_irq_on - switch on tx irq on this spider card
+ * spider_net_rx_irq_on - switch on rx irq on this spider card
  * @card: device structure
  *
- * switches on tx irq by enabling them in the GHIINTnMSK register
+ * switches on rx irq by enabling them in the GHIINTnMSK register
  */
 static void
-spider_net_tx_irq_on(struct spider_net_card *card)
+spider_net_rx_irq_on(struct spider_net_card *card)
 {
        u32 regvalue;
-       unsigned long flags;
 
-       spin_lock_irqsave(&card->intmask_lock, flags);
-       regvalue = spider_net_read_reg(card, SPIDER_NET_GHIINT0MSK);
-       regvalue |= SPIDER_NET_TXINT;
-       spider_net_write_reg_sync(card, SPIDER_NET_GHIINT0MSK, regvalue);
-       spin_unlock_irqrestore(&card->intmask_lock, flags);
+       regvalue = SPIDER_NET_INT0_MASK_VALUE | SPIDER_NET_RXINT;
+       spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK, regvalue);
 }
 
 /**
@@ -322,42 +262,10 @@ spider_net_get_mac_address(struct net_device *netdev)
  *
  * returns the status as in the dmac_cmd_status field of the descriptor
  */
-static enum spider_net_descr_status
+static inline int
 spider_net_get_descr_status(struct spider_net_descr *descr)
 {
-       u32 cmd_status;
-       rmb();
-       cmd_status = descr->dmac_cmd_status;
-       rmb();
-       cmd_status >>= SPIDER_NET_DESCR_IND_PROC_SHIFT;
-       /* no need to mask out any bits, as cmd_status is 32 bits wide only
-        * (and unsigned) */
-       return cmd_status;
-}
-
-/**
- * spider_net_set_descr_status -- sets the status of a descriptor
- * @descr: descriptor to change
- * @status: status to set in the descriptor
- *
- * changes the status to the specified value. Doesn't change other bits
- * in the status
- */
-static void
-spider_net_set_descr_status(struct spider_net_descr *descr,
-                           enum spider_net_descr_status status)
-{
-       u32 cmd_status;
-       /* read the status */
-       mb();
-       cmd_status = descr->dmac_cmd_status;
-       /* clean the upper 4 bits */
-       cmd_status &= SPIDER_NET_DESCR_IND_PROC_MASKO;
-       /* add the status to it */
-       cmd_status |= ((u32)status)<<SPIDER_NET_DESCR_IND_PROC_SHIFT;
-       /* and write it back */
-       descr->dmac_cmd_status = cmd_status;
-       wmb();
+       return descr->dmac_cmd_status & SPIDER_NET_DESCR_IND_PROC_MASK;
 }
 
 /**
@@ -372,75 +280,67 @@ spider_net_free_chain(struct spider_net_card *card,
 {
        struct spider_net_descr *descr;
 
-       for (descr = chain->tail; !descr->bus_addr; descr = descr->next) {
-               pci_unmap_single(card->pdev, descr->bus_addr,
-                                SPIDER_NET_DESCR_SIZE, PCI_DMA_BIDIRECTIONAL);
+       descr = chain->ring;
+       do {
                descr->bus_addr = 0;
-       }
+               descr->next_descr_addr = 0;
+               descr = descr->next;
+       } while (descr != chain->ring);
+
+       dma_free_coherent(&card->pdev->dev, chain->num_desc,
+           chain->ring, chain->dma_addr);
 }
 
 /**
- * spider_net_init_chain - links descriptor chain
+ * spider_net_init_chain - alloc and link descriptor chain
  * @card: card structure
  * @chain: address of chain
- * @start_descr: address of descriptor array
- * @no: number of descriptors
  *
- * we manage a circular list that mirrors the hardware structure,
+ * We manage a circular list that mirrors the hardware structure,
  * except that the hardware uses bus addresses.
  *
- * returns 0 on success, <0 on failure
+ * Returns 0 on success, <0 on failure
  */
 static int
 spider_net_init_chain(struct spider_net_card *card,
-                      struct spider_net_descr_chain *chain,
-                      struct spider_net_descr *start_descr, int no)
+                      struct spider_net_descr_chain *chain)
 {
        int i;
        struct spider_net_descr *descr;
+       dma_addr_t buf;
+       size_t alloc_size;
 
-       spin_lock_init(&card->chain_lock);
+       alloc_size = chain->num_desc * sizeof (struct spider_net_descr);
 
-       descr = start_descr;
-       memset(descr, 0, sizeof(*descr) * no);
+       chain->ring = dma_alloc_coherent(&card->pdev->dev, alloc_size,
+               &chain->dma_addr, GFP_KERNEL);
 
-       /* set up the hardware pointers in each descriptor */
-       for (i=0; i<no; i++, descr++) {
-               spider_net_set_descr_status(descr, SPIDER_NET_DESCR_NOT_IN_USE);
+       if (!chain->ring)
+               return -ENOMEM;
 
-               descr->bus_addr =
-                       pci_map_single(card->pdev, descr,
-                                      SPIDER_NET_DESCR_SIZE,
-                                      PCI_DMA_BIDIRECTIONAL);
+       descr = chain->ring;
+       memset(descr, 0, alloc_size);
 
-               if (descr->bus_addr == DMA_ERROR_CODE)
-                       goto iommu_error;
+       /* Set up the hardware pointers in each descriptor */
+       buf = chain->dma_addr;
+       for (i=0; i < chain->num_desc; i++, descr++) {
+               descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
 
+               descr->bus_addr = buf;
+               descr->next_descr_addr = 0;
                descr->next = descr + 1;
                descr->prev = descr - 1;
 
+               buf += sizeof(struct spider_net_descr);
        }
        /* do actual circular list */
-       (descr-1)->next = start_descr;
-       start_descr->prev = descr-1;
-
-       descr = start_descr;
-       for (i=0; i < no; i++, descr++) {
-               descr->next_descr_addr = descr->next->bus_addr;
-       }
-
-       chain->head = start_descr;
-       chain->tail = start_descr;
+       (descr-1)->next = chain->ring;
+       chain->ring->prev = descr-1;
 
+       spin_lock_init(&chain->lock);
+       chain->head = chain->ring;
+       chain->tail = chain->ring;
        return 0;
-
-iommu_error:
-       descr = start_descr;
-       for (i=0; i < no; i++, descr++)
-               if (descr->bus_addr)
-                       pci_unmap_single(card->pdev, descr->bus_addr,
-                                        SPIDER_NET_DESCR_SIZE, PCI_DMA_BIDIRECTIONAL);
-       return -ENOMEM;
 }
 
 /**
@@ -455,37 +355,37 @@ spider_net_free_rx_chain_contents(struct spider_net_card *card)
        struct spider_net_descr *descr;
 
        descr = card->rx_chain.head;
-       while (descr->next != card->rx_chain.head) {
+       do {
                if (descr->skb) {
                        dev_kfree_skb(descr->skb);
                        pci_unmap_single(card->pdev, descr->buf_addr,
-                                        SPIDER_NET_MAX_MTU,
+                                        SPIDER_NET_MAX_FRAME,
                                         PCI_DMA_BIDIRECTIONAL);
                }
                descr = descr->next;
-       }
+       } while (descr != card->rx_chain.head);
 }
 
 /**
- * spider_net_prepare_rx_descr - reinitializes a rx descriptor
+ * spider_net_prepare_rx_descr - Reinitialize RX descriptor
  * @card: card structure
  * @descr: descriptor to re-init
  *
- * return 0 on succes, <0 on failure
+ * Return 0 on succes, <0 on failure.
  *
- * allocates a new rx skb, iommu-maps it and attaches it to the descriptor.
- * Activate the descriptor state-wise
+ * Allocates a new rx skb, iommu-maps it and attaches it to the
+ * descriptor. Mark the descriptor as activated, ready-to-use.
  */
 static int
 spider_net_prepare_rx_descr(struct spider_net_card *card,
                            struct spider_net_descr *descr)
 {
-       int error = 0;
+       dma_addr_t buf;
        int offset;
        int bufsize;
 
        /* we need to round up the buffer size to a multiple of 128 */
-       bufsize = (SPIDER_NET_MAX_MTU + SPIDER_NET_RXBUF_ALIGN - 1) &
+       bufsize = (SPIDER_NET_MAX_FRAME + SPIDER_NET_RXBUF_ALIGN - 1) &
                (~(SPIDER_NET_RXBUF_ALIGN - 1));
 
        /* and we need to have it 128 byte aligned, therefore we allocate a
@@ -493,10 +393,9 @@ spider_net_prepare_rx_descr(struct spider_net_card *card,
        /* allocate an skb */
        descr->skb = dev_alloc_skb(bufsize + SPIDER_NET_RXBUF_ALIGN - 1);
        if (!descr->skb) {
-               if (net_ratelimit())
-                       if (netif_msg_rx_err(card))
-                               pr_err("Not enough memory to allocate "
-                                       "rx buffer\n");
+               if (netif_msg_rx_err(card) && net_ratelimit())
+                       pr_err("Not enough memory to allocate rx buffer\n");
+               card->spider_stats.alloc_rx_skb_error++;
                return -ENOMEM;
        }
        descr->buf_size = bufsize;
@@ -509,31 +408,34 @@ spider_net_prepare_rx_descr(struct spider_net_card *card,
                (SPIDER_NET_RXBUF_ALIGN - 1);
        if (offset)
                skb_reserve(descr->skb, SPIDER_NET_RXBUF_ALIGN - offset);
-       /* io-mmu-map the skb */
-       descr->buf_addr = pci_map_single(card->pdev, descr->skb->data,
-                                        SPIDER_NET_MAX_MTU,
-                                        PCI_DMA_BIDIRECTIONAL);
-       if (descr->buf_addr == DMA_ERROR_CODE) {
+       /* iommu-map the skb */
+       buf = pci_map_single(card->pdev, descr->skb->data,
+                       SPIDER_NET_MAX_FRAME, PCI_DMA_FROMDEVICE);
+       descr->buf_addr = buf;
+       if (pci_dma_mapping_error(buf)) {
                dev_kfree_skb_any(descr->skb);
-               if (netif_msg_rx_err(card))
+               if (netif_msg_rx_err(card) && net_ratelimit())
                        pr_err("Could not iommu-map rx buffer\n");
-               spider_net_set_descr_status(descr, SPIDER_NET_DESCR_NOT_IN_USE);
+               card->spider_stats.rx_iommu_map_error++;
+               descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
        } else {
-               descr->dmac_cmd_status = SPIDER_NET_DMAC_RX_CARDOWNED;
+               wmb();
+               descr->dmac_cmd_status = SPIDER_NET_DESCR_CARDOWNED |
+                                        SPIDER_NET_DMAC_NOINTR_COMPLETE;
        }
 
-       return error;
+       return 0;
 }
 
 /**
- * spider_net_enable_rxctails - sets RX dmac chain tail addresses
+ * spider_net_enable_rxchtails - sets RX dmac chain tail addresses
  * @card: card structure
  *
- * spider_net_enable_rxctails sets the RX DMAC chain tail adresses in the
+ * spider_net_enable_rxchtails sets the RX DMAC chain tail adresses in the
  * chip by writing to the appropriate register. DMA is enabled in
  * spider_net_enable_rxdmac.
  */
-static void
+static inline void
 spider_net_enable_rxchtails(struct spider_net_card *card)
 {
        /* assume chain is aligned correctly */
@@ -548,9 +450,10 @@ spider_net_enable_rxchtails(struct spider_net_card *card)
  * spider_net_enable_rxdmac enables the DMA controller by setting RX_DMA_EN
  * in the GDADMACCNTR register
  */
-static void
+static inline void
 spider_net_enable_rxdmac(struct spider_net_card *card)
 {
+       wmb();
        spider_net_write_reg(card, SPIDER_NET_GDADMACCNTR,
                             SPIDER_NET_DMA_RX_VALUE);
 }
@@ -559,39 +462,36 @@ spider_net_enable_rxdmac(struct spider_net_card *card)
  * spider_net_refill_rx_chain - refills descriptors/skbs in the rx chains
  * @card: card structure
  *
- * refills descriptors in all chains (last used chain first): allocates skbs
- * and iommu-maps them.
+ * refills descriptors in the rx chain: allocates skbs and iommu-maps them.
  */
 static void
 spider_net_refill_rx_chain(struct spider_net_card *card)
 {
-       struct spider_net_descr_chain *chain;
-       int count = 0;
+       struct spider_net_descr_chain *chain = &card->rx_chain;
        unsigned long flags;
 
-       chain = &card->rx_chain;
+       /* one context doing the refill (and a second context seeing that
+        * and omitting it) is ok. If called by NAPI, we'll be called again
+        * as spider_net_decode_one_descr is called several times. If some
+        * interrupt calls us, the NAPI is about to clean up anyway. */
+       if (!spin_trylock_irqsave(&chain->lock, flags))
+               return;
 
-       spin_lock_irqsave(&card->chain_lock, flags);
        while (spider_net_get_descr_status(chain->head) ==
-                               SPIDER_NET_DESCR_NOT_IN_USE) {
+                       SPIDER_NET_DESCR_NOT_IN_USE) {
                if (spider_net_prepare_rx_descr(card, chain->head))
                        break;
-               count++;
                chain->head = chain->head->next;
        }
-       spin_unlock_irqrestore(&card->chain_lock, flags);
 
-       /* could be optimized, only do that, if we know the DMA processing
-        * has terminated */
-       if (count)
-               spider_net_enable_rxdmac(card);
+       spin_unlock_irqrestore(&chain->lock, flags);
 }
 
 /**
- * spider_net_alloc_rx_skbs - allocates rx skbs in rx descriptor chains
+ * spider_net_alloc_rx_skbs - Allocates rx skbs in rx descriptor chains
  * @card: card structure
  *
- * returns 0 on success, <0 on failure
+ * Returns 0 on success, <0 on failure.
  */
 static int
 spider_net_alloc_rx_skbs(struct spider_net_card *card)
@@ -602,17 +502,18 @@ spider_net_alloc_rx_skbs(struct spider_net_card *card)
        result = -ENOMEM;
 
        chain = &card->rx_chain;
-       /* put at least one buffer into the chain. if this fails,
-        * we've got a problem. if not, spider_net_refill_rx_chain
-        * will do the rest at the end of this function */
+       /* Put at least one buffer into the chain. if this fails,
+        * we've got a problem. If not, spider_net_refill_rx_chain
+        * will do the rest at the end of this function. */
        if (spider_net_prepare_rx_descr(card, chain->head))
                goto error;
        else
                chain->head = chain->head->next;
 
-       /* this will allocate the rest of the rx buffers; if not, it's
-        * business as usual later on */
+       /* This will allocate the rest of the rx buffers;
+        * if not, it's business as usual later on. */
        spider_net_refill_rx_chain(card);
+       spider_net_enable_rxdmac(card);
        return 0;
 
 error:
@@ -621,100 +522,6 @@ error:
 }
 
 /**
- * spider_net_release_tx_descr - processes a used tx descriptor
- * @card: card structure
- * @descr: descriptor to release
- *
- * releases a used tx descriptor (unmapping, freeing of skb)
- */
-static void
-spider_net_release_tx_descr(struct spider_net_card *card,
-                           struct spider_net_descr *descr)
-{
-       struct sk_buff *skb;
-
-       /* unmap the skb */
-       skb = descr->skb;
-       pci_unmap_single(card->pdev, descr->buf_addr, skb->len,
-                        PCI_DMA_BIDIRECTIONAL);
-
-       dev_kfree_skb_any(skb);
-
-       /* set status to not used */
-       spider_net_set_descr_status(descr, SPIDER_NET_DESCR_NOT_IN_USE);
-}
-
-/**
- * spider_net_release_tx_chain - processes sent tx descriptors
- * @card: adapter structure
- * @brutal: if set, don't care about whether descriptor seems to be in use
- *
- * releases the tx descriptors that spider has finished with (if non-brutal)
- * or simply release tx descriptors (if brutal)
- */
-static void
-spider_net_release_tx_chain(struct spider_net_card *card, int brutal)
-{
-       struct spider_net_descr_chain *tx_chain = &card->tx_chain;
-       enum spider_net_descr_status status;
-
-       spider_net_tx_irq_off(card);
-
-       /* no lock for chain needed, if this is only executed once at a time */
-again:
-       for (;;) {
-               status = spider_net_get_descr_status(tx_chain->tail);
-               switch (status) {
-               case SPIDER_NET_DESCR_CARDOWNED:
-                       if (!brutal) goto out;
-                       /* fallthrough, if we release the descriptors
-                        * brutally (then we don't care about
-                        * SPIDER_NET_DESCR_CARDOWNED) */
-               case SPIDER_NET_DESCR_RESPONSE_ERROR:
-               case SPIDER_NET_DESCR_PROTECTION_ERROR:
-               case SPIDER_NET_DESCR_FORCE_END:
-                       if (netif_msg_tx_err(card))
-                               pr_err("%s: forcing end of tx descriptor "
-                                      "with status x%02x\n",
-                                      card->netdev->name, status);
-                       card->netdev_stats.tx_dropped++;
-                       break;
-
-               case SPIDER_NET_DESCR_COMPLETE:
-                       card->netdev_stats.tx_packets++;
-                       card->netdev_stats.tx_bytes +=
-                               tx_chain->tail->skb->len;
-                       break;
-
-               default: /* any other value (== SPIDER_NET_DESCR_NOT_IN_USE) */
-                       goto out;
-               }
-               spider_net_release_tx_descr(card, tx_chain->tail);
-               tx_chain->tail = tx_chain->tail->next;
-       }
-out:
-       netif_wake_queue(card->netdev);
-
-       if (!brutal) {
-               /* switch on tx irqs (while we are still in the interrupt
-                * handler, so we don't get an interrupt), check again
-                * for done descriptors. This results in fewer interrupts */
-               spider_net_tx_irq_on(card);
-               status = spider_net_get_descr_status(tx_chain->tail);
-               switch (status) {
-                       case SPIDER_NET_DESCR_RESPONSE_ERROR:
-                       case SPIDER_NET_DESCR_PROTECTION_ERROR:
-                       case SPIDER_NET_DESCR_FORCE_END:
-                       case SPIDER_NET_DESCR_COMPLETE:
-                               goto again;
-                       default:
-                               break;
-               }
-       }
-
-}
-
-/**
  * spider_net_get_multicast_hash - generates hash for multicast filter table
  * @addr: multicast address
  *
@@ -726,16 +533,22 @@ out:
 static u8
 spider_net_get_multicast_hash(struct net_device *netdev, __u8 *addr)
 {
-       /* FIXME: an addr of 01:00:5e:00:00:01 must result in 0xa9,
-        * ff:ff:ff:ff:ff:ff must result in 0xfd */
        u32 crc;
        u8 hash;
+       char addr_for_crc[ETH_ALEN] = { 0, };
+       int i, bit;
+
+       for (i = 0; i < ETH_ALEN * 8; i++) {
+               bit = (addr[i / 8] >> (i % 8)) & 1;
+               addr_for_crc[ETH_ALEN - 1 - i / 8] += bit << (7 - (i % 8));
+       }
 
-       crc = crc32_be(~0, addr, netdev->addr_len);
+       crc = crc32_be(~0, addr_for_crc, netdev->addr_len);
 
        hash = (crc >> 27);
        hash <<= 3;
        hash |= crc & 7;
+       hash &= 0xff;
 
        return hash;
 }
@@ -811,128 +624,178 @@ spider_net_disable_rxdmac(struct spider_net_card *card)
 }
 
 /**
- * spider_net_stop - called upon ifconfig down
- * @netdev: interface device structure
+ * spider_net_prepare_tx_descr - fill tx descriptor with skb data
+ * @card: card structure
+ * @descr: descriptor structure to fill out
+ * @skb: packet to use
  *
- * always returns 0
+ * returns 0 on success, <0 on failure.
+ *
+ * fills out the descriptor structure with skb data and len. Copies data,
+ * if needed (32bit DMA!)
  */
-int
-spider_net_stop(struct net_device *netdev)
+static int
+spider_net_prepare_tx_descr(struct spider_net_card *card,
+                           struct sk_buff *skb)
 {
-       struct spider_net_card *card = netdev_priv(netdev);
-
-       netif_poll_disable(netdev);
-       netif_carrier_off(netdev);
-       netif_stop_queue(netdev);
+       struct spider_net_descr *descr;
+       dma_addr_t buf;
+       unsigned long flags;
 
-       /* disable/mask all interrupts */
-       spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK, 0);
-       spider_net_write_reg(card, SPIDER_NET_GHIINT1MSK, 0);
-       spider_net_write_reg(card, SPIDER_NET_GHIINT2MSK, 0);
+       buf = pci_map_single(card->pdev, skb->data, skb->len, PCI_DMA_TODEVICE);
+       if (pci_dma_mapping_error(buf)) {
+               if (netif_msg_tx_err(card) && net_ratelimit())
+                       pr_err("could not iommu-map packet (%p, %i). "
+                                 "Dropping packet\n", skb->data, skb->len);
+               card->spider_stats.tx_iommu_map_error++;
+               return -ENOMEM;
+       }
 
-       /* free_irq(netdev->irq, netdev);*/
-       free_irq(to_pci_dev(netdev->class_dev.dev)->irq, netdev);
+       spin_lock_irqsave(&card->tx_chain.lock, flags);
+       descr = card->tx_chain.head;
+       card->tx_chain.head = descr->next;
 
-       spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
-                            SPIDER_NET_DMA_TX_FEND_VALUE);
+       descr->buf_addr = buf;
+       descr->buf_size = skb->len;
+       descr->next_descr_addr = 0;
+       descr->skb = skb;
+       descr->data_status = 0;
 
-       /* turn off DMA, force end */
-       spider_net_disable_rxdmac(card);
+       descr->dmac_cmd_status =
+                       SPIDER_NET_DESCR_CARDOWNED | SPIDER_NET_DMAC_NOCS;
+       spin_unlock_irqrestore(&card->tx_chain.lock, flags);
 
-       /* release chains */
-       spider_net_release_tx_chain(card, 1);
+       if (skb->protocol == htons(ETH_P_IP))
+               switch (skb->nh.iph->protocol) {
+               case IPPROTO_TCP:
+                       descr->dmac_cmd_status |= SPIDER_NET_DMAC_TCP;
+                       break;
+               case IPPROTO_UDP:
+                       descr->dmac_cmd_status |= SPIDER_NET_DMAC_UDP;
+                       break;
+               }
 
-       spider_net_free_chain(card, &card->tx_chain);
-       spider_net_free_chain(card, &card->rx_chain);
+       /* Chain the bus address, so that the DMA engine finds this descr. */
+       descr->prev->next_descr_addr = descr->bus_addr;
 
+       card->netdev->trans_start = jiffies; /* set netdev watchdog timer */
        return 0;
 }
 
-/**
- * spider_net_get_next_tx_descr - returns the next available tx descriptor
- * @card: device structure to get descriptor from
- *
- * returns the address of the next descriptor, or NULL if not available.
- */
-static struct spider_net_descr *
-spider_net_get_next_tx_descr(struct spider_net_card *card)
+static int
+spider_net_set_low_watermark(struct spider_net_card *card)
 {
-       /* check, if head points to not-in-use descr */
-       if ( spider_net_get_descr_status(card->tx_chain.head) ==
-            SPIDER_NET_DESCR_NOT_IN_USE ) {
-               return card->tx_chain.head;
-       } else {
-               return NULL;
-       }
-}
+       unsigned long flags;
+       int status;
+       int cnt=0;
+       int i;
+       struct spider_net_descr *descr = card->tx_chain.tail;
 
-/**
- * spider_net_set_txdescr_cmdstat - sets the tx descriptor command field
- * @descr: descriptor structure to fill out
- * @skb: packet to consider
- *
- * fills out the command and status field of the descriptor structure,
- * depending on hardware checksum settings. This function assumes a wmb()
- * has executed before.
- */
-static void
-spider_net_set_txdescr_cmdstat(struct spider_net_descr *descr,
-                              struct sk_buff *skb)
-{
-       if (skb->ip_summed != CHECKSUM_HW) {
-               descr->dmac_cmd_status = SPIDER_NET_DMAC_CMDSTAT_NOCS;
-               return;
+       /* Measure the length of the queue. Measurement does not
+        * need to be precise -- does not need a lock. */
+       while (descr != card->tx_chain.head) {
+               status = descr->dmac_cmd_status & SPIDER_NET_DESCR_NOT_IN_USE;
+               if (status == SPIDER_NET_DESCR_NOT_IN_USE)
+                       break;
+               descr = descr->next;
+               cnt++;
        }
 
-       /* is packet ip?
-        * if yes: tcp? udp? */
-       if (skb->protocol == htons(ETH_P_IP)) {
-               if (skb->nh.iph->protocol == IPPROTO_TCP) {
-                       descr->dmac_cmd_status = SPIDER_NET_DMAC_CMDSTAT_TCPCS;
-               } else if (skb->nh.iph->protocol == IPPROTO_UDP) {
-                       descr->dmac_cmd_status = SPIDER_NET_DMAC_CMDSTAT_UDPCS;
-               } else { /* the stack should checksum non-tcp and non-udp
-                           packets on his own: NETIF_F_IP_CSUM */
-                       descr->dmac_cmd_status = SPIDER_NET_DMAC_CMDSTAT_NOCS;
-               }
-       }
+       /* If TX queue is short, don't even bother with interrupts */
+       if (cnt < card->tx_chain.num_desc/4)
+               return cnt;
+
+       /* Set low-watermark 3/4th's of the way into the queue. */
+       descr = card->tx_chain.tail;
+       cnt = (cnt*3)/4;
+       for (i=0;i<cnt; i++)
+               descr = descr->next;
+
+       /* Set the new watermark, clear the old watermark */
+       spin_lock_irqsave(&card->tx_chain.lock, flags);
+       descr->dmac_cmd_status |= SPIDER_NET_DESCR_TXDESFLG;
+       if (card->low_watermark && card->low_watermark != descr)
+               card->low_watermark->dmac_cmd_status =
+                    card->low_watermark->dmac_cmd_status & ~SPIDER_NET_DESCR_TXDESFLG;
+       card->low_watermark = descr;
+       spin_unlock_irqrestore(&card->tx_chain.lock, flags);
+       return cnt;
 }
 
 /**
- * spider_net_prepare_tx_descr - fill tx descriptor with skb data
- * @card: card structure
- * @descr: descriptor structure to fill out
- * @skb: packet to use
+ * spider_net_release_tx_chain - processes sent tx descriptors
+ * @card: adapter structure
+ * @brutal: if set, don't care about whether descriptor seems to be in use
  *
- * returns 0 on success, <0 on failure.
+ * returns 0 if the tx ring is empty, otherwise 1.
  *
- * fills out the descriptor structure with skb data and len. Copies data,
- * if needed (32bit DMA!)
+ * spider_net_release_tx_chain releases the tx descriptors that spider has
+ * finished with (if non-brutal) or simply release tx descriptors (if brutal).
+ * If some other context is calling this function, we return 1 so that we're
+ * scheduled again (if we were scheduled) and will not loose initiative.
  */
 static int
-spider_net_prepare_tx_descr(struct spider_net_card *card,
-                           struct spider_net_descr *descr,
-                           struct sk_buff *skb)
+spider_net_release_tx_chain(struct spider_net_card *card, int brutal)
 {
-       descr->buf_addr = pci_map_single(card->pdev, skb->data,
-                                        skb->len, PCI_DMA_BIDIRECTIONAL);
-       if (descr->buf_addr == DMA_ERROR_CODE) {
-               if (netif_msg_tx_err(card))
-                       pr_err("could not iommu-map packet (%p, %i). "
-                                 "Dropping packet\n", skb->data, skb->len);
-               return -ENOMEM;
-       }
+       struct spider_net_descr_chain *chain = &card->tx_chain;
+       struct spider_net_descr *descr;
+       struct sk_buff *skb;
+       u32 buf_addr;
+       unsigned long flags;
+       int status;
 
-       descr->buf_size = skb->len;
-       descr->skb = skb;
-       descr->data_status = 0;
+       while (chain->tail != chain->head) {
+               spin_lock_irqsave(&chain->lock, flags);
+               descr = chain->tail;
 
-       /* make sure the above values are in memory before we change the
-        * status */
-       wmb();
+               status = spider_net_get_descr_status(descr);
+               switch (status) {
+               case SPIDER_NET_DESCR_COMPLETE:
+                       card->netdev_stats.tx_packets++;
+                       card->netdev_stats.tx_bytes += descr->skb->len;
+                       break;
 
-       spider_net_set_txdescr_cmdstat(descr,skb);
+               case SPIDER_NET_DESCR_CARDOWNED:
+                       if (!brutal) {
+                               spin_unlock_irqrestore(&chain->lock, flags);
+                               return 1;
+                       }
 
+                       /* fallthrough, if we release the descriptors
+                        * brutally (then we don't care about
+                        * SPIDER_NET_DESCR_CARDOWNED) */
+
+               case SPIDER_NET_DESCR_RESPONSE_ERROR:
+               case SPIDER_NET_DESCR_PROTECTION_ERROR:
+               case SPIDER_NET_DESCR_FORCE_END:
+                       if (netif_msg_tx_err(card))
+                               pr_err("%s: forcing end of tx descriptor "
+                                      "with status x%02x\n",
+                                      card->netdev->name, status);
+                       card->netdev_stats.tx_errors++;
+                       break;
+
+               default:
+                       card->netdev_stats.tx_dropped++;
+                       if (!brutal) {
+                               spin_unlock_irqrestore(&chain->lock, flags);
+                               return 1;
+                       }
+               }
+
+               chain->tail = descr->next;
+               descr->dmac_cmd_status |= SPIDER_NET_DESCR_NOT_IN_USE;
+               skb = descr->skb;
+               buf_addr = descr->buf_addr;
+               spin_unlock_irqrestore(&chain->lock, flags);
+
+               /* unmap the skb */
+               if (skb) {
+                       pci_unmap_single(card->pdev, buf_addr, skb->len,
+                                       PCI_DMA_TODEVICE);
+                       dev_kfree_skb(skb);
+               }
+       }
        return 0;
 }
 
@@ -941,21 +804,39 @@ spider_net_prepare_tx_descr(struct spider_net_card *card,
  * @card: card structure
  * @descr: descriptor address to enable TX processing at
  *
- * spider_net_kick_tx_dma writes the current tx chain head as start address
- * of the tx descriptor chain and enables the transmission DMA engine
+ * This routine will start the transmit DMA running if
+ * it is not already running. This routine ned only be
+ * called when queueing a new packet to an empty tx queue.
+ * Writes the current tx chain head as start address
+ * of the tx descriptor chain and enables the transmission
+ * DMA engine.
  */
-static void
-spider_net_kick_tx_dma(struct spider_net_card *card,
-                      struct spider_net_descr *descr)
+static inline void
+spider_net_kick_tx_dma(struct spider_net_card *card)
 {
-       /* this is the only descriptor in the output chain.
-        * Enable TX DMA */
+       struct spider_net_descr *descr;
 
-       spider_net_write_reg(card, SPIDER_NET_GDTDCHA,
-                            descr->bus_addr);
+       if (spider_net_read_reg(card, SPIDER_NET_GDTDMACCNTR) &
+                       SPIDER_NET_TX_DMA_EN)
+               goto out;
 
-       spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
-                            SPIDER_NET_DMA_TX_VALUE);
+       descr = card->tx_chain.tail;
+       for (;;) {
+               if (spider_net_get_descr_status(descr) ==
+                               SPIDER_NET_DESCR_CARDOWNED) {
+                       spider_net_write_reg(card, SPIDER_NET_GDTDCHA,
+                                       descr->bus_addr);
+                       spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
+                                       SPIDER_NET_DMA_TX_VALUE);
+                       break;
+               }
+               if (descr == card->tx_chain.head)
+                       break;
+               descr = descr->next;
+       }
+
+out:
+       mod_timer(&card->tx_timer, jiffies + SPIDER_NET_TX_TIMER);
 }
 
 /**
@@ -963,46 +844,48 @@ spider_net_kick_tx_dma(struct spider_net_card *card,
  * @skb: packet to send out
  * @netdev: interface device structure
  *
- * returns 0 on success, <0 on failure
+ * returns 0 on success, !0 on failure
  */
 static int
 spider_net_xmit(struct sk_buff *skb, struct net_device *netdev)
 {
+       int cnt;
        struct spider_net_card *card = netdev_priv(netdev);
-       struct spider_net_descr *descr;
-       int result;
+       struct spider_net_descr_chain *chain = &card->tx_chain;
 
-       descr = spider_net_get_next_tx_descr(card);
+       spider_net_release_tx_chain(card, 0);
 
-       if (!descr) {
-               netif_stop_queue(netdev);
+       if ((chain->head->next == chain->tail->prev) ||
+          (spider_net_prepare_tx_descr(card, skb) != 0)) {
 
-               descr = spider_net_get_next_tx_descr(card);
-               if (!descr)
-                       goto error;
-               else
-                       netif_start_queue(netdev);
+               card->netdev_stats.tx_dropped++;
+               netif_stop_queue(netdev);
+               return NETDEV_TX_BUSY;
        }
 
-       result = spider_net_prepare_tx_descr(card, descr, skb);
-       if (result)
-               goto error;
-
-       card->tx_chain.head = card->tx_chain.head->next;
-
-       /* make sure the status from spider_net_prepare_tx_descr is in
-        * memory before we check out the previous descriptor */
-       wmb();
-
-       if (spider_net_get_descr_status(descr->prev) !=
-           SPIDER_NET_DESCR_CARDOWNED)
-               spider_net_kick_tx_dma(card, descr);
-
+       cnt = spider_net_set_low_watermark(card);
+       if (cnt < 5)
+               spider_net_kick_tx_dma(card);
        return NETDEV_TX_OK;
+}
 
-error:
-       card->netdev_stats.tx_dropped++;
-       return NETDEV_TX_LOCKED;
+/**
+ * spider_net_cleanup_tx_ring - cleans up the TX ring
+ * @card: card structure
+ *
+ * spider_net_cleanup_tx_ring is called by either the tx_timer
+ * or from the NAPI polling routine.
+ * This routine releases resources associted with transmitted
+ * packets, including updating the queue tail pointer.
+ */
+static void
+spider_net_cleanup_tx_ring(struct spider_net_card *card)
+{
+       if ((spider_net_release_tx_chain(card, 0) != 0) &&
+           (card->netdev->flags & IFF_UP)) {
+               spider_net_kick_tx_dma(card);
+               netif_wake_queue(card->netdev);
+       }
 }
 
 /**
@@ -1028,12 +911,10 @@ spider_net_do_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
  * @descr: descriptor to process
  * @card: card structure
  *
- * returns 1 on success, 0 if no packet was passed to the stack
- *
- * iommu-unmaps the skb, fills out skb structure and passes the data to the
- * stack. The descriptor state is not changed.
+ * Fills out skb structure and passes the data to the stack.
+ * The descriptor state is not changed.
  */
-static int
+static void
 spider_net_pass_skb_up(struct spider_net_descr *descr,
                       struct spider_net_card *card)
 {
@@ -1043,25 +924,9 @@ spider_net_pass_skb_up(struct spider_net_descr *descr,
 
        data_status = descr->data_status;
        data_error = descr->data_error;
-
        netdev = card->netdev;
 
-       /* check for errors in the data_error flag */
-       if ((data_error & SPIDER_NET_DATA_ERROR_MASK) &&
-           netif_msg_rx_err(card))
-               pr_err("error in received descriptor found, "
-                      "data_status=x%08x, data_error=x%08x\n",
-                      data_status, data_error);
-
-       /* prepare skb, unmap descriptor */
        skb = descr->skb;
-       pci_unmap_single(card->pdev, descr->buf_addr, SPIDER_NET_MAX_MTU,
-                        PCI_DMA_BIDIRECTIONAL);
-
-       /* the cases we'll throw away the packet immediately */
-       if (data_error & SPIDER_NET_DESTROY_RX_FLAGS)
-               return 0;
-
        skb->dev = netdev;
        skb_put(skb, descr->valid_size);
 
@@ -1073,14 +938,14 @@ spider_net_pass_skb_up(struct spider_net_descr *descr,
 
        /* checksum offload */
        if (card->options.rx_csum) {
-               if ( (data_status & SPIDER_NET_DATA_STATUS_CHK_MASK) &&
-                    (!(data_error & SPIDER_NET_DATA_ERROR_CHK_MASK)) )
+               if ( ( (data_status & SPIDER_NET_DATA_STATUS_CKSUM_MASK) ==
+                      SPIDER_NET_DATA_STATUS_CKSUM_MASK) &&
+                    !(data_error & SPIDER_NET_DATA_ERR_CKSUM_MASK))
                        skb->ip_summed = CHECKSUM_UNNECESSARY;
                else
                        skb->ip_summed = CHECKSUM_NONE;
-       } else {
+       } else
                skb->ip_summed = CHECKSUM_NONE;
-       }
 
        if (data_status & SPIDER_NET_VLAN_PACKET) {
                /* further enhancements: HW-accel VLAN
@@ -1094,48 +959,67 @@ spider_net_pass_skb_up(struct spider_net_descr *descr,
        /* update netdevice statistics */
        card->netdev_stats.rx_packets++;
        card->netdev_stats.rx_bytes += skb->len;
+}
 
-       return 1;
+#ifdef DEBUG
+static void show_rx_chain(struct spider_net_card *card)
+{
+       struct spider_net_descr_chain *chain = &card->rx_chain;
+       struct spider_net_descr *start= chain->tail;
+       struct spider_net_descr *descr= start;
+       int status;
+
+       int cnt = 0;
+       int cstat = spider_net_get_descr_status(descr);
+       printk(KERN_INFO "RX chain tail at descr=%ld\n",
+            (start - card->descr) - card->tx_chain.num_desc);
+       status = cstat;
+       do
+       {
+               status = spider_net_get_descr_status(descr);
+               if (cstat != status) {
+                       printk(KERN_INFO "Have %d descrs with stat=x%08x\n", cnt, cstat);
+                       cstat = status;
+                       cnt = 0;
+               }
+               cnt ++;
+               descr = descr->next;
+       } while (descr != start);
+       printk(KERN_INFO "Last %d descrs with stat=x%08x\n", cnt, cstat);
 }
+#endif
 
 /**
- * spider_net_decode_descr - processes an rx descriptor
+ * spider_net_decode_one_descr - processes an rx descriptor
  * @card: card structure
  *
- * returns 1 if a packet has been sent to the stack, otherwise 0
+ * Returns 1 if a packet has been sent to the stack, otherwise 0
  *
- * processes an rx descriptor by iommu-unmapping the data buffer and passing
- * the packet up to the stack
+ * Processes an rx descriptor by iommu-unmapping the data buffer and passing
+ * the packet up to the stack. This function is called in softirq
+ * context, e.g. either bottom half from interrupt or NAPI polling context
  */
 static int
 spider_net_decode_one_descr(struct spider_net_card *card)
 {
-       enum spider_net_descr_status status;
-       struct spider_net_descr *descr;
-       struct spider_net_descr_chain *chain;
-       int result;
-
-       chain = &card->rx_chain;
-       descr = chain->tail;
+       struct spider_net_descr_chain *chain = &card->rx_chain;
+       struct spider_net_descr *descr = chain->tail;
+       int status;
 
        status = spider_net_get_descr_status(descr);
 
-       if (status == SPIDER_NET_DESCR_CARDOWNED) {
-               /* nothing in the descriptor yet */
+       /* Nothing in the descriptor, or ring must be empty */
+       if ((status == SPIDER_NET_DESCR_CARDOWNED) ||
+           (status == SPIDER_NET_DESCR_NOT_IN_USE))
                return 0;
-       }
-
-       if (status == SPIDER_NET_DESCR_NOT_IN_USE) {
-               /* not initialized yet, I bet chain->tail == chain->head
-                * and the ring is empty */
-               spider_net_refill_rx_chain(card);
-               return 0;
-       }
 
-       /* descriptor definitively used -- move on head */
+       /* descriptor definitively used -- move on tail */
        chain->tail = descr->next;
 
-       result = 0;
+       /* unmap descriptor */
+       pci_unmap_single(card->pdev, descr->buf_addr,
+                       SPIDER_NET_MAX_FRAME, PCI_DMA_FROMDEVICE);
+
        if ( (status == SPIDER_NET_DESCR_RESPONSE_ERROR) ||
             (status == SPIDER_NET_DESCR_PROTECTION_ERROR) ||
             (status == SPIDER_NET_DESCR_FORCE_END) ) {
@@ -1143,25 +1027,55 @@ spider_net_decode_one_descr(struct spider_net_card *card)
                        pr_err("%s: dropping RX descriptor with state %d\n",
                               card->netdev->name, status);
                card->netdev_stats.rx_dropped++;
-               goto refill;
+               goto bad_desc;
        }
 
        if ( (status != SPIDER_NET_DESCR_COMPLETE) &&
             (status != SPIDER_NET_DESCR_FRAME_END) ) {
                if (netif_msg_rx_err(card))
-                       pr_err("%s: RX descriptor with state %d\n",
+                       pr_err("%s: RX descriptor with unkown state %d\n",
                               card->netdev->name, status);
-               goto refill;
+               card->spider_stats.rx_desc_unk_state++;
+               goto bad_desc;
        }
 
-       /* ok, we've got a packet in descr */
-       result = spider_net_pass_skb_up(descr, card);
-refill:
-       spider_net_set_descr_status(descr, SPIDER_NET_DESCR_NOT_IN_USE);
-       /* change the descriptor state: */
-       spider_net_refill_rx_chain(card);
+       /* The cases we'll throw away the packet immediately */
+       if (descr->data_error & SPIDER_NET_DESTROY_RX_FLAGS) {
+               if (netif_msg_rx_err(card))
+                       pr_err("%s: error in received descriptor found, "
+                              "data_status=x%08x, data_error=x%08x\n",
+                              card->netdev->name,
+                              descr->data_status, descr->data_error);
+               goto bad_desc;
+       }
 
-       return result;
+       if (descr->dmac_cmd_status & 0xfefe) {
+               pr_err("%s: bad status, cmd_status=x%08x\n",
+                              card->netdev->name,
+                              descr->dmac_cmd_status);
+               pr_err("buf_addr=x%08x\n", descr->buf_addr);
+               pr_err("buf_size=x%08x\n", descr->buf_size);
+               pr_err("next_descr_addr=x%08x\n", descr->next_descr_addr);
+               pr_err("result_size=x%08x\n", descr->result_size);
+               pr_err("valid_size=x%08x\n", descr->valid_size);
+               pr_err("data_status=x%08x\n", descr->data_status);
+               pr_err("data_error=x%08x\n", descr->data_error);
+               pr_err("bus_addr=x%08x\n", descr->bus_addr);
+               pr_err("which=%ld\n", descr - card->rx_chain.ring);
+
+               card->spider_stats.rx_desc_error++;
+               goto bad_desc;
+       }
+
+       /* Ok, we've got a packet in descr */
+       spider_net_pass_skb_up(descr, card);
+       descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
+       return 1;
+
+bad_desc:
+       dev_kfree_skb_irq(descr->skb);
+       descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
+       return 0;
 }
 
 /**
@@ -1183,6 +1097,7 @@ spider_net_poll(struct net_device *netdev, int *budget)
        int packets_to_do, packets_done = 0;
        int no_more_packets = 0;
 
+       spider_net_cleanup_tx_ring(card);
        packets_to_do = min(*budget, netdev->quota);
 
        while (packets_to_do) {
@@ -1198,6 +1113,8 @@ spider_net_poll(struct net_device *netdev, int *budget)
 
        netdev->quota -= packets_done;
        *budget -= packets_done;
+       spider_net_refill_rx_chain(card);
+       spider_net_enable_rxdmac(card);
 
        /* if all packets are in the stack, enable interrupts and return 0 */
        /* if not, return 1 */
@@ -1327,21 +1244,6 @@ spider_net_set_mac(struct net_device *netdev, void *p)
 }
 
 /**
- * spider_net_enable_txdmac - enables a TX DMA controller
- * @card: card structure
- *
- * spider_net_enable_txdmac enables the TX DMA controller by setting the
- * descriptor chain tail address
- */
-static void
-spider_net_enable_txdmac(struct spider_net_card *card)
-{
-       /* assume chain is aligned correctly */
-       spider_net_write_reg(card, SPIDER_NET_GDTDCHA,
-                            card->tx_chain.tail->bus_addr);
-}
-
-/**
  * spider_net_handle_error_irq - handles errors raised by an interrupt
  * @card: card structure
  * @status_reg: interrupt status register 0 (GHIINT0STS)
@@ -1369,12 +1271,15 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
        case SPIDER_NET_PHYINT:
        case SPIDER_NET_GMAC2INT:
        case SPIDER_NET_GMAC1INT:
-       case SPIDER_NET_GIPSINT:
        case SPIDER_NET_GFIFOINT:
        case SPIDER_NET_DMACINT:
        case SPIDER_NET_GSYSINT:
                break; */
 
+       case SPIDER_NET_GIPSINT:
+               show_error = 0;
+               break;
+
        case SPIDER_NET_GPWOPCMPINT:
                /* PHY write operation completed */
                show_error = 0;
@@ -1433,9 +1338,10 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
        case SPIDER_NET_GDTDCEINT:
                /* chain end. If a descriptor should be sent, kick off
                 * tx dma
-               if (card->tx_chain.tail == card->tx_chain.head)
+               if (card->tx_chain.tail != card->tx_chain.head)
                        spider_net_kick_tx_dma(card);
-               show_error = 0; */
+               */
+               show_error = 0;
                break;
 
        /* case SPIDER_NET_G1TMCNTINT: not used. print a message */
@@ -1449,17 +1355,21 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
                                switch (i)
        {
        case SPIDER_NET_GTMFLLINT:
-               if (netif_msg_intr(card))
+               if (netif_msg_intr(card) && net_ratelimit())
                        pr_err("Spider TX RAM full\n");
                show_error = 0;
                break;
+       case SPIDER_NET_GRFDFLLINT: /* fallthrough */
+       case SPIDER_NET_GRFCFLLINT: /* fallthrough */
+       case SPIDER_NET_GRFBFLLINT: /* fallthrough */
+       case SPIDER_NET_GRFAFLLINT: /* fallthrough */
        case SPIDER_NET_GRMFLLINT:
-               if (netif_msg_intr(card))
+               if (netif_msg_intr(card) && net_ratelimit())
                        pr_err("Spider RX RAM full, incoming packets "
-                              "might be discarded !\n");
+                              "might be discarded!\n");
+               spider_net_rx_irq_off(card);
                netif_rx_schedule(card->netdev);
-               spider_net_enable_rxchtails(card);
-               spider_net_enable_rxdmac(card);
+               show_error = 0;
                break;
 
        /* case SPIDER_NET_GTMSHTINT: problem, print a message */
@@ -1467,21 +1377,18 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
                /* allrighty. tx from previous descr ok */
                show_error = 0;
                break;
-       /* case SPIDER_NET_GRFDFLLINT: print a message down there */
-       /* case SPIDER_NET_GRFCFLLINT: print a message down there */
-       /* case SPIDER_NET_GRFBFLLINT: print a message down there */
-       /* case SPIDER_NET_GRFAFLLINT: print a message down there */
 
        /* chain end */
        case SPIDER_NET_GDDDCEINT: /* fallthrough */
        case SPIDER_NET_GDCDCEINT: /* fallthrough */
        case SPIDER_NET_GDBDCEINT: /* fallthrough */
        case SPIDER_NET_GDADCEINT:
-               if (netif_msg_intr(card))
+               if (netif_msg_intr(card) && net_ratelimit())
                        pr_err("got descriptor chain end interrupt, "
                               "restarting DMAC %c.\n",
-                              'D'+i-SPIDER_NET_GDDDCEINT);
+                              'D'-(i-SPIDER_NET_GDDDCEINT)/3);
                spider_net_refill_rx_chain(card);
+               spider_net_enable_rxdmac(card);
                show_error = 0;
                break;
 
@@ -1492,6 +1399,7 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
        case SPIDER_NET_GDAINVDINT:
                /* could happen when rx chain is full */
                spider_net_refill_rx_chain(card);
+               spider_net_enable_rxdmac(card);
                show_error = 0;
                break;
 
@@ -1546,9 +1454,10 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
                        break;
        }
 
-       if ((show_error) && (netif_msg_intr(card)))
-               pr_err("Got error interrupt, GHIINT0STS = 0x%08x, "
+       if ((show_error) && (netif_msg_intr(card)) && net_ratelimit())
+               pr_err("Got error interrupt on %s, GHIINT0STS = 0x%08x, "
                       "GHIINT1STS = 0x%08x, GHIINT2STS = 0x%08x\n",
+                      card->netdev->name,
                       status_reg, error_reg1, error_reg2);
 
        /* clear interrupt sources */
@@ -1569,7 +1478,7 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
  * interrupts for this device and makes the stack poll the driver
  */
 static irqreturn_t
-spider_net_interrupt(int irq, void *ptr, struct pt_regs *regs)
+spider_net_interrupt(int irq, void *ptr)
 {
        struct net_device *netdev = ptr;
        struct spider_net_card *card = netdev_priv(netdev);
@@ -1580,17 +1489,15 @@ spider_net_interrupt(int irq, void *ptr, struct pt_regs *regs)
        if (!status_reg)
                return IRQ_NONE;
 
-       if (status_reg & SPIDER_NET_TXINT)
-               spider_net_release_tx_chain(card, 0);
-
        if (status_reg & SPIDER_NET_RXINT ) {
                spider_net_rx_irq_off(card);
                netif_rx_schedule(netdev);
        }
+       if (status_reg & SPIDER_NET_TXINT)
+               netif_rx_schedule(netdev);
 
-       /* we do this after rx and tx processing, as we want the tx chain
-        * processed to see, whether we should restart tx dma processing */
-       spider_net_handle_error_irq(card, status_reg);
+       if (status_reg & SPIDER_NET_ERRINT )
+               spider_net_handle_error_irq(card, status_reg);
 
        /* clear interrupt sources */
        spider_net_write_reg(card, SPIDER_NET_GHIINT0STS, status_reg);
@@ -1609,7 +1516,7 @@ static void
 spider_net_poll_controller(struct net_device *netdev)
 {
        disable_irq(netdev->irq);
-       spider_net_interrupt(netdev->irq, netdev, NULL);
+       spider_net_interrupt(netdev->irq, netdev);
        enable_irq(netdev->irq);
 }
 #endif /* CONFIG_NET_POLL_CONTROLLER */
@@ -1671,7 +1578,8 @@ spider_net_enable_card(struct spider_net_card *card)
                { SPIDER_NET_GFTRESTRT, SPIDER_NET_RESTART_VALUE },
 
                { SPIDER_NET_GMRWOLCTRL, 0 },
-               { SPIDER_NET_GTESTMD, 0 },
+               { SPIDER_NET_GTESTMD, 0x10000000 },
+               { SPIDER_NET_GTTQMSK, 0x00400040 },
 
                { SPIDER_NET_GMACINTEN, 0 },
 
@@ -1710,9 +1618,6 @@ spider_net_enable_card(struct spider_net_card *card)
 
        spider_net_write_reg(card, SPIDER_NET_GRXDMAEN, SPIDER_NET_WOL_VALUE);
 
-       /* set chain tail adress for TX chain */
-       spider_net_enable_txdmac(card);
-
        spider_net_write_reg(card, SPIDER_NET_GMACLENLMT,
                             SPIDER_NET_LENLMT_VALUE);
        spider_net_write_reg(card, SPIDER_NET_GMACMODE,
@@ -1727,6 +1632,9 @@ spider_net_enable_card(struct spider_net_card *card)
                             SPIDER_NET_INT1_MASK_VALUE);
        spider_net_write_reg(card, SPIDER_NET_GHIINT2MSK,
                             SPIDER_NET_INT2_MASK_VALUE);
+
+       spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
+                            SPIDER_NET_GDTBSTA);
 }
 
 /**
@@ -1742,17 +1650,26 @@ int
 spider_net_open(struct net_device *netdev)
 {
        struct spider_net_card *card = netdev_priv(netdev);
+       struct spider_net_descr *descr;
        int result;
 
-       result = -ENOMEM;
-       if (spider_net_init_chain(card, &card->tx_chain,
-                         card->descr, tx_descriptors))
+       result = spider_net_init_chain(card, &card->tx_chain);
+       if (result)
                goto alloc_tx_failed;
-       if (spider_net_init_chain(card, &card->rx_chain,
-                         card->descr + tx_descriptors, rx_descriptors))
+       card->low_watermark = NULL;
+
+       result = spider_net_init_chain(card, &card->rx_chain);
+       if (result)
                goto alloc_rx_failed;
 
-       /* allocate rx skbs */
+       /* Make a ring of of bus addresses */
+       descr = card->rx_chain.ring;
+       do {
+               descr->next_descr_addr = descr->next->bus_addr;
+               descr = descr->next;
+       } while (descr != card->rx_chain.ring);
+
+       /* Allocate rx skbs */
        if (spider_net_alloc_rx_skbs(card))
                goto alloc_skbs_failed;
 
@@ -1762,7 +1679,7 @@ spider_net_open(struct net_device *netdev)
 
        result = -EBUSY;
        if (request_irq(netdev->irq, spider_net_interrupt,
-                            SA_SHIRQ, netdev->name, netdev))
+                            IRQF_SHARED, netdev->name, netdev))
                goto register_int_failed;
 
        spider_net_enable_card(card);
@@ -1811,15 +1728,7 @@ spider_net_setup_phy(struct spider_net_card *card)
        if (phy->def->ops->setup_forced)
                phy->def->ops->setup_forced(phy, SPEED_1000, DUPLEX_FULL);
 
-       /* the following two writes could be moved to sungem_phy.c */
-       /* enable fiber mode */
-       spider_net_write_phy(card->netdev, 1, MII_NCONFIG, 0x9020);
-       /* LEDs active in both modes, autosense prio = fiber */
-       spider_net_write_phy(card->netdev, 1, MII_NCONFIG, 0x945f);
-
-       /* switch off fibre autoneg */
-       spider_net_write_phy(card->netdev, 1, MII_NCONFIG, 0xfc01);
-       spider_net_write_phy(card->netdev, 1, 0x0b, 0x0004);
+       phy->def->ops->enable_fiber(phy);
 
        phy->def->ops->read_link(phy);
        pr_info("Found %s with %i Mbps, %s-duplex.\n", phy->def->name,
@@ -1831,26 +1740,27 @@ spider_net_setup_phy(struct spider_net_card *card)
 /**
  * spider_net_download_firmware - loads firmware into the adapter
  * @card: card structure
- * @firmware: firmware pointer
+ * @firmware_ptr: pointer to firmware data
  *
- * spider_net_download_firmware loads the firmware opened by
- * spider_net_init_firmware into the adapter.
+ * spider_net_download_firmware loads the firmware data into the
+ * adapter. It assumes the length etc. to be allright.
  */
 static int
 spider_net_download_firmware(struct spider_net_card *card,
-                            const struct firmware *firmware)
+                            const void *firmware_ptr)
 {
        int sequencer, i;
-       u32 *fw_ptr = (u32 *)firmware->data;
+       const u32 *fw_ptr = firmware_ptr;
 
        /* stop sequencers */
        spider_net_write_reg(card, SPIDER_NET_GSINIT,
                             SPIDER_NET_STOP_SEQ_VALUE);
 
-       for (sequencer = 0; sequencer < 6; sequencer++) {
+       for (sequencer = 0; sequencer < SPIDER_NET_FIRMWARE_SEQS;
+            sequencer++) {
                spider_net_write_reg(card,
                                     SPIDER_NET_GSnPRGADR + sequencer * 8, 0);
-               for (i = 0; i < SPIDER_NET_FIRMWARE_LEN; i++) {
+               for (i = 0; i < SPIDER_NET_FIRMWARE_SEQWORDS; i++) {
                        spider_net_write_reg(card, SPIDER_NET_GSnPRGDAT +
                                             sequencer * 8, *fw_ptr);
                        fw_ptr++;
@@ -1895,30 +1805,53 @@ spider_net_download_firmware(struct spider_net_card *card,
 static int
 spider_net_init_firmware(struct spider_net_card *card)
 {
-       const struct firmware *firmware;
-       int err = -EIO;
+       struct firmware *firmware = NULL;
+       struct device_node *dn;
+       const u8 *fw_prop = NULL;
+       int err = -ENOENT;
+       int fw_size;
+
+       if (request_firmware((const struct firmware **)&firmware,
+                            SPIDER_NET_FIRMWARE_NAME, &card->pdev->dev) == 0) {
+               if ( (firmware->size != SPIDER_NET_FIRMWARE_LEN) &&
+                    netif_msg_probe(card) ) {
+                       pr_err("Incorrect size of spidernet firmware in " \
+                              "filesystem. Looking in host firmware...\n");
+                       goto try_host_fw;
+               }
+               err = spider_net_download_firmware(card, firmware->data);
 
-       if (request_firmware(&firmware,
-                            SPIDER_NET_FIRMWARE_NAME, &card->pdev->dev) < 0) {
-               if (netif_msg_probe(card))
-                       pr_err("Couldn't read in sequencer data file %s.\n",
-                              SPIDER_NET_FIRMWARE_NAME);
-               firmware = NULL;
-               goto out;
+               release_firmware(firmware);
+               if (err)
+                       goto try_host_fw;
+
+               goto done;
        }
 
-       if (firmware->size != 6 * SPIDER_NET_FIRMWARE_LEN * sizeof(u32)) {
-               if (netif_msg_probe(card))
-                       pr_err("Invalid size of sequencer data file %s.\n",
-                              SPIDER_NET_FIRMWARE_NAME);
-               goto out;
+try_host_fw:
+       dn = pci_device_to_OF_node(card->pdev);
+       if (!dn)
+               goto out_err;
+
+       fw_prop = get_property(dn, "firmware", &fw_size);
+       if (!fw_prop)
+               goto out_err;
+
+       if ( (fw_size != SPIDER_NET_FIRMWARE_LEN) &&
+            netif_msg_probe(card) ) {
+               pr_err("Incorrect size of spidernet firmware in " \
+                      "host firmware\n");
+               goto done;
        }
 
-       if (!spider_net_download_firmware(card, firmware))
-               err = 0;
-out:
-       release_firmware(firmware);
+       err = spider_net_download_firmware(card, fw_prop);
 
+done:
+       return err;
+out_err:
+       if (netif_msg_probe(card))
+               pr_err("Couldn't find spidernet firmware in filesystem " \
+                      "or host firmware\n");
        return err;
 }
 
@@ -1938,10 +1871,11 @@ spider_net_workaround_rxramfull(struct spider_net_card *card)
                             SPIDER_NET_CKRCTRL_RUN_VALUE);
 
        /* empty sequencer data */
-       for (sequencer = 0; sequencer < 6; sequencer++) {
-               spider_net_write_reg(card, SPIDER_NET_GSnPRGDAT +
+       for (sequencer = 0; sequencer < SPIDER_NET_FIRMWARE_SEQS;
+            sequencer++) {
+               spider_net_write_reg(card, SPIDER_NET_GSnPRGADR +
                                     sequencer * 8, 0x0);
-               for (i = 0; i < SPIDER_NET_FIRMWARE_LEN; i++) {
+               for (i = 0; i < SPIDER_NET_FIRMWARE_SEQWORDS; i++) {
                        spider_net_write_reg(card, SPIDER_NET_GSnPRGDAT +
                                             sequencer * 8, 0x0);
                }
@@ -1956,6 +1890,48 @@ spider_net_workaround_rxramfull(struct spider_net_card *card)
 }
 
 /**
+ * spider_net_stop - called upon ifconfig down
+ * @netdev: interface device structure
+ *
+ * always returns 0
+ */
+int
+spider_net_stop(struct net_device *netdev)
+{
+       struct spider_net_card *card = netdev_priv(netdev);
+
+       netif_poll_disable(netdev);
+       netif_carrier_off(netdev);
+       netif_stop_queue(netdev);
+       del_timer_sync(&card->tx_timer);
+
+       /* disable/mask all interrupts */
+       spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK, 0);
+       spider_net_write_reg(card, SPIDER_NET_GHIINT1MSK, 0);
+       spider_net_write_reg(card, SPIDER_NET_GHIINT2MSK, 0);
+
+       /* free_irq(netdev->irq, netdev);*/
+       free_irq(to_pci_dev(netdev->class_dev.dev)->irq, netdev);
+
+       spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
+                            SPIDER_NET_DMA_TX_FEND_VALUE);
+
+       /* turn off DMA, force end */
+       spider_net_disable_rxdmac(card);
+
+       /* release chains */
+       spider_net_release_tx_chain(card, 1);
+       spider_net_free_rx_chain_contents(card);
+
+       spider_net_free_rx_chain_contents(card);
+
+       spider_net_free_chain(card, &card->tx_chain);
+       spider_net_free_chain(card, &card->rx_chain);
+
+       return 0;
+}
+
+/**
  * spider_net_tx_timeout_task - task scheduled by the watchdog timeout
  * function (to be called not under interrupt status)
  * @data: data, is interface device structure
@@ -1963,10 +1939,11 @@ spider_net_workaround_rxramfull(struct spider_net_card *card)
  * called as task when tx hangs, resets interface (if interface is up)
  */
 static void
-spider_net_tx_timeout_task(void *data)
+spider_net_tx_timeout_task(struct work_struct *work)
 {
-       struct net_device *netdev = data;
-       struct spider_net_card *card = netdev_priv(netdev);
+       struct spider_net_card *card =
+               container_of(work, struct spider_net_card, tx_timeout_task);
+       struct net_device *netdev = card->netdev;
 
        if (!(netdev->flags & IFF_UP))
                goto out;
@@ -1983,7 +1960,7 @@ spider_net_tx_timeout_task(void *data)
                goto out;
 
        spider_net_open(netdev);
-       spider_net_kick_tx_dma(card, card->tx_chain.head);
+       spider_net_kick_tx_dma(card);
        netif_device_attach(netdev);
 
 out:
@@ -2007,6 +1984,7 @@ spider_net_tx_timeout(struct net_device *netdev)
                schedule_work(&card->tx_timeout_task);
        else
                atomic_dec(&card->tx_timeout_task_counter);
+       card->spider_stats.tx_timeouts++;
 }
 
 /**
@@ -2059,20 +2037,27 @@ spider_net_setup_netdev(struct spider_net_card *card)
        struct net_device *netdev = card->netdev;
        struct device_node *dn;
        struct sockaddr addr;
-       u8 *mac;
+       const u8 *mac;
 
        SET_MODULE_OWNER(netdev);
        SET_NETDEV_DEV(netdev, &card->pdev->dev);
 
        pci_set_drvdata(card->pdev, netdev);
-       spin_lock_init(&card->intmask_lock);
+
+       init_timer(&card->tx_timer);
+       card->tx_timer.function =
+               (void (*)(unsigned long)) spider_net_cleanup_tx_ring;
+       card->tx_timer.data = (unsigned long) card;
        netdev->irq = card->pdev->irq;
 
        card->options.rx_csum = SPIDER_NET_RX_CSUM_DEFAULT;
 
+       card->tx_chain.num_desc = tx_descriptors;
+       card->rx_chain.num_desc = rx_descriptors;
+
        spider_net_setup_netdev_ops(netdev);
 
-       netdev->features = 0;
+       netdev->features = NETIF_F_HW_CSUM | NETIF_F_LLTX;
        /* some time: NETIF_F_HW_VLAN_TX | NETIF_F_HW_VLAN_RX |
         *              NETIF_F_HW_VLAN_FILTER */
 
@@ -2082,7 +2067,7 @@ spider_net_setup_netdev(struct spider_net_card *card)
        if (!dn)
                return -EIO;
 
-       mac = (u8 *)get_property(dn, "local-mac-address", NULL);
+       mac = get_property(dn, "local-mac-address", NULL);
        if (!mac)
                return -EIO;
        memcpy(addr.sa_data, mac, ETH_ALEN);
@@ -2117,19 +2102,15 @@ spider_net_alloc_card(void)
 {
        struct net_device *netdev;
        struct spider_net_card *card;
-       size_t alloc_size;
 
-       alloc_size = sizeof (*card) +
-               sizeof (struct spider_net_descr) * rx_descriptors +
-               sizeof (struct spider_net_descr) * tx_descriptors;
-       netdev = alloc_etherdev(alloc_size);
+       netdev = alloc_etherdev(sizeof(struct spider_net_card));
        if (!netdev)
                return NULL;
 
        card = netdev_priv(netdev);
        card->netdev = netdev;
        card->msg_enable = SPIDER_NET_DEFAULT_MSG;
-       INIT_WORK(&card->tx_timeout_task, spider_net_tx_timeout_task, netdev);
+       INIT_WORK(&card->tx_timeout_task, spider_net_tx_timeout_task);
        init_waitqueue_head(&card->waitq);
        atomic_set(&card->tx_timeout_task_counter, 0);
 
@@ -2307,6 +2288,8 @@ static struct pci_driver spider_net_driver = {
  */
 static int __init spider_net_init(void)
 {
+       printk(KERN_INFO "Spidernet version %s.\n", VERSION);
+
        if (rx_descriptors < SPIDER_NET_RX_DESCRIPTORS_MIN) {
                rx_descriptors = SPIDER_NET_RX_DESCRIPTORS_MIN;
                pr_info("adjusting rx descriptors to %i.\n", rx_descriptors);